Process for producing a potato granule p product from commercial potato flakes and potato granules



United States Patent Othce 3,457,088 Patented July 22, 1969 3,457,088PROCESS FOR PRODUCING A POTATO GRANULE PRODUCT FROM COMMERCIAL POTATOFLAKES AND POTATO GRANULES Roderick G. Beck, Blackfoot, Idaho, assignorto American Potato Company No Drawing. Filed Apr. 14, 1966, Ser. No.542,462

Int. (:1. A23! 1/12 U.S. c1. 99-207 7 3 Claims ABSTRACT OF THEDISCLOSURE This invention relates to a new process for manufacturingpotato granules and more particularly to a process which utilizes amixture of potato flakes and potato granules to produce a fine granularproduct with the performance characteristics of potato granules producedby the add-back process.

- Two types of dehydrated potato products from which instant mashedpotatoes can be made by reconstitution in liquid have met withacceptance by housewives, institutions, and the Armed Forces. Potatogranules and potato flakes are both produced commercially in largeamounts. The advantages and disadvantages of both are discussedthoroughly in the prior art such as U.S. Patents. Nos. 3,067,042;2,988,543; 3,063,849; and 3,021,223. These can be summarized as follows:

Potato flakes (commercial density about 15 lbs. [cu. ft.])

(1) Low density is an advantage in housewife applications.

(2) Can be reconstituted in cold liquid for specialized applicationssuch as frozen TV dinners.

Potato granules (commercial density about 5 6 lbs. [cu. ft.])

Advantages:

(1) High density is an advantage for Armed Forces and most institutionaluses.

(2) High density allows eflicient inert gas packaging which aids storagestability.

(3) Potato granules can be reconstituted in boiling liquid and can standwhipping without creating poor texture or pastiness.

Disadvantages:

(1) High density undesirable for retail sale and use.

(2) Will not reconstitute in cold liquid.

The prior art cited above deals with processes and products whichattempt to retain the natural advantages and reduce or eliminate thedisadvantages of commercial potato flakes.

In U.S. No. 3,067,042, potato flakes are broken to increase the bulkdensity. The fine fraction which would cause pastiness and starchinessis screened out and added to the mash of the subsequent lot. Precookingand monoglycerides are said to allow this to be done without excessivetexture degradation if the percentage of fines is not too high.

In U.S. No. 3,063,849 potato flakes are also ground to pass /8 inch.Stickiness which would result from the breaking step is nullified by afinal heating step which retrogrades the free soluble starch. The finalheated product has a baked potato flavor and is said to be excellent insoups.

In U.S. No. 2,980,543 potato flakes are broken and an improver issprayed on the dry broken flakes to counteract the stickiness created bybreaking.

In U.S. No. 3,021,223 potato flakes are broken and then are increased inmoisture and manipulated to produce products of increased density. Ifthe moisture is inv 15 lbs./cu. ft. to 35-52 lbs/cu. ft. The end productconsists of thick small flakes called flakelets.

Although the processes disclosed in the prior art have resulted inincreasing the bulk density of potato flakes, I have found thatdesirable characteristics have been lost. When dry potato flakes arereduced in size until the density is comparable to that of potatogranules, the large quantities of free starch formed causes pastiness inthe reconstituted mash even with the use of improvers. When rupturedcells are returned to a fresh mash, even precooking and the use ofmonoglyceride allow only a small percentage of free starch to betolerated without pastiness. When excessive heat is used on brokenflakes to accomplish retrogradation of soluble free starch, flavor ischanged. Furthermore, starch retrogradation reduces water uptake anddestroys the ability to reconstitute in cold liquid. Any processing stepconducted at high moisture and room temperature incorporated with anyappreciable holding time will result in retrogradation and theinevitable loss of desirable rehydration characteristics.

The object of the present invention is to produce by a continuous andpractical process a dried potato product with all the advantages ofpotato granules, using commercial potato flakes as the principalstarting ingredient in the process.

Since one of the major differences between the flake and granuleprocesses is the absence of a retrogradation step in the flake processand the necessity of retro gradation in the granule process to attainproper granulation, a study of the effect of (a) moisture content, (b)time, and (0) temperature of retrogradation on cold water absorption wasmade.

When 100% of 8 mesh potato flakes as well as various mixtures of 8 meshpotato flakes and potato granules were moistened to 42% moisture, mixed,conditioned by standing one hour at room temperature, mixed, and dried,substantial differences were obvious. The dry end product made from -8mesh flakes alone was very coarse in granulation -50% failed to pass a20 mesh screen and only 14% passed an mesh screen. The use of 8 meshpotato flakes to produce a fine end product was.

poor reconstitution characteristics that it would be com merciallyunacceptable. The suggested processing step 1n.

the prior art of foring the coarse fraction through a 0.023 inch openingafter sieving the moist mix over a 20 mesh screen is not only extremelydamaging to the sensitive potato cells but commercially completelyimpractical. In contrast, when one part by Weight potato granules wasmixed with three parts by weight of 8 mesh potato flakes and handled inexactly the same manner, a very fine damp powder which could be directlydried without further treatment was obtained. The incorporation of aminor percentage of potato granules had 4 20 mesh screen. This producthad a'density of about 44 lbs./cu. ft. and more than 30% passed astandard 80 mesh screen. If a 20 mesh product is the desired finalproduct the small percentage of coarser fraction could be rewet alongwith the potato flakes in a continuous surprisingly resulted in a vastlyimproved product and 5 process. This eliminates the necessity of forcingthe damp process. mix through fine openings such as .023" which would beA second series of tests was run using various moisdamaging to thepotato cells and is a processing step ture levels between 25 and 45% forre-wetting the mixwhich would be commercially impractical. The endprodture of 75% -8 mesh potato flakes and 25% potato 10 not from thisprocess has excellent flavor and texture and granules prior to finaldehydration. All mixes were has all the advantages of potatogranules-being'capable allowed to condition y Standing at roomtemperature of boiling water reconstrutcion and capable of whipping for0116 hour, followed y a Second mixing p l Prior without texture damage.This product is much finer to final drying with the following results:than could-be obtained by partially reconstituting potato flakes aloneand processing them in a comparable Granulation cold water manner. Byadding all the reconstitution water to the R'ewet rehydmion potato flakefraction alone, the advantages of higher T moisture moistures wereobtained-namely, easier flake break- 25 59 16 u down to potato cells andsmall agglomerates and faster 61 9 20 retrogradation. By adding the drypotato granules after 2o 67 13 Fall. 36 56 a Poor. partialretrogradation, the moisture content of the mix 25 64 21 Very is reducedthereby creating a friable mix which does not The results obtained werecompletely unexpected. 2:23. g i i izf and results In a largerPercentage of The literature indicates that the retrogradation ofsoluble 25 B d h th f 1 potato amylose proceeds most rapidly at about29% y 15 process/an wlt e 3 mon o a moisture: however in these tests, Ifound the higher few pieces of conventional equipment, a conventionalmoistures apparently promoted the conversion to insolu- Potato flakeplant can be convirted produce a prodlfct ble amylose and destroyed theability of the resulting very potato granules mappeamnce and denslty dryproduct to rehydrate satisfactorily in cold Watch 30 and with all theadvantages of potato granules and none The lower moisture contents f 5and 0% gave of the disadvantages of potato flakes. The potato flakescomparable granulation and i h case f h f used as the starting materialcould be made by the accepted retained the ability of the original flakecompotechniques now in use in potato flake manufacture innent torehydrate in cold water. At 30% moisture, eluding precooking and coolingprior to cooking and the the abiltiy to rehydrate in cold water wasmostly re- 35 addition of accepted additives such as emulsifiers,sultained. Apparently, no appreciable retrogradation took phites, andanti-oxidants. place at these lower moisture levels. l l i A thirdseries tests was run using a 75% 8 potato 1. A process for producingpotato granules from flake-25% potato granule mix at 40% moisture.Mixpotato flakes without formation of inadmissible amounts ing wasidentical to previous tests but the conditioning 4 of free starchcomprising the steps of moistening potato times and temperatures werevaried With the following flakes sufliciently to form a smooth, damp,non-particuresults: late mix; equilibrating said mix; adding dry potatoCondition- Granulation Cold water Conditioning ing temperrehydrationTest No time ature F.) +20 --20 +80 --80 (5;1)

s. 0 68 28 4 Excellent. 16. 15 minutes. 70 42 8 Good. 17. 30 minutes. 7026 64 10 Fair.

140 29 61 10 Goci di The results here were as expected. The literatureindigranules to provide a substantial minor fraction of the cates thatincreased time at decreased temperatures entotal potato solids in themix to reduce the moisture courages retrogradation of potato amylose. Inevery case, thereof to not less than about 30% and to produce agranulation improved and cold water rehydration was moist friableintermediate; thoroughly mixing and allowreduced with increases of timeor decreases of temperaing the intermediate to retrograde at roomtemperature; me Although, prolonged holding at F. gave a mixing theretrograded intermediate; and drying the receptable granulation, theability to reconstitute in cold sulting damp powder to produce a potatogranule product. Water Was lmpalfed Somewhat 2. The process of claim 1in which the-potato solids We then tested our process with still anothervariation. dd d as granules amounts about 25% f the totaL Instead ofmixing the --8 mesh flakes and the granules 3. The process of claim 1 inwhich the moisture of dry before rewetting, we used the same amount oftotal th i i i l flake i i about 45% water applied first to the flakeportion and we were able to produce a product with all the desirablecharacteristics of potato granules. Standard commercial potato flakesReferences cued were uniformly moistened with cold water to 46% mois-UNITED STATES PATENTS r ture. The moistened flakes were then allowed toequili- 65 3,275,45 9 1955 win 99 207 brate and retrograde for 30minutes. The wet flakes were u then mixed with dry commercial potatogranules equal .OTHERREFERENCES in wei ht to one-third the solids of theflakes. The moisture of the mix was now 40% as before and the source ofEskew et Potato Flakes Increased Denslty' September 1960 ARS73-30, Agnc.Res. Ser. U.S.-D.A.

the potato solids was still 75 flakes-25% granules. The moist mix wasthen allowed to stand one hour before mixing again to further granulatethe product. The mix was then dried and screened over a 20 mesh screen.Approximately of the dried product passed through the (pp. 4-7) I LIONELM. SHAPIRO, Primary Examiner 75 D. M. NAFF, Assistant Examiner

